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J Schulz

Publications and source records attributed to J Schulz.

At least 37 records · Page 2Linked to original sources
PubMed2001

Assessment of the resonance thromboelastograph CS-3 for differentiation of coagulation disorders: a pilot in vitro investigation of simulated post-cardiopulmonary bypass coagulopathies.

Resonance thromboelastography (RTG), a further development of the thromboelastogram (TEG), has been designed for improved differentiation of the effect of the plasmatic coagulation factors (increasing F-leg) and platelets (decreasing P-leg) on clot formation. It is based on the effect of clot elasticity on the resonance of a swinging wire. We assessed the RTG for its ability to differentiate coagulation disorders that frequently occur after cardiac surgery. The RTG was performed with a CS-3 Analyzer. Samples from 10 healthy volunteers were investigated after the following preparations: (1) baseline values, (2) dilution to a hematocrit of 30% and 20% with either hydroxyl ethyl starch (HES) 10% or plasma; (3) addition of 0.25, 0.5, and 1.0 IU/mL porcine heparin with and without heparinase; and (4) addition of 1.0, 3.0, 4.0, and 5.0 microg/mL of the antiplatelet agent abciximab (ReoPro). Increasing concentrations of abciximab led to a slower decrease or in the case of higher concentrations, to a persistent elevation of the platelet leg of the RTG. Dilution of the hematocrit with plasma had no effect on the fibrin and platelet leg; whereas, dilution with HES 10% led to an inhibition of the fibrin and platelet leg. Dilution of the plasmatic coagulation factors resulted in an inhibition of both the fibrin and the platelet leg. The addition of 0.25 and 0.5 IU/mL of heparin led to an increased coagulation time and inhibition of the fibrin and platelet legs. These effects were eliminated by the addition of heparinase. The RTG enables the evaluation of platelet function under the condition of a nonimpaired plasma coagulation system. Depletion of plasma coagulation factors and the administration of small amounts of heparin do not enable the distinction between residual effects of an anticoagulant, coagulation factor deficiency, or impaired platelet function. However, the heparin effects can be eliminated by the addition of heparinase. Further improvement may be achieved using a modified RTG by adding plasma coagulation factors in one channel for an improved evaluation of platelet function, even under the condition of a loss of procoagulants.

Abciximab↗
PubMed2000

Stabilized rhodium(0) nanoparticles: a reusable hydrogenation catalyst for arene derivatives in a biphasic water-liquid system.

A colloidal system based on an aqueous suspension of rhodium(o) nanoparticles proved to be an efficient catalyst for the hydrogenation of arene derivatives under biphasic conditions. The rhodium nanoparticles (2-2.5 nm) were synthesized by the reduction of RhCl3 x 3H2O with sodium borohydride and were stabilized by highly water-soluble N-alkyl-N-(2-hydroxyethyl)ammonium salts (HEA-Cn). These surfactant molecules were characterized by measurements of the surface tension and the aqueous dispersions with rhodium were observed by transmission electron cryomicroscopy. The catalytic system is efficient under ultramild conditions, namely room temperature and 1 atm H2 pressure. The aqueous phase which contains the protected rhodium(0) colloids can be reused without significant loss of activity. The microheterogeneous behavior of this catalytic system was confirmed on a mercury poisoning experiment.

Catalysis↗
PubMed2000

LF16-0687 a novel non-peptide bradykinin B2 receptor antagonist reduces vasogenic brain edema from a focal lesion in rats.

Head injury world wide is still the most frequent cause of morbidity and mortality among the population under 45 years. Approximately 50% of patients dying from severe head injury have a therapy refractory intracranial pressure rise (Baethmann 1998). Traumatic brain edema, e.g. resulting from disruption of the blood-brain barrier is viewed as an important factor of the increased intracranial pressure. Bradykinin, an active peptide of the kallikrein-kinin system is considered to enhance brain edema formation which is attributed to its permeabilizing effect on the blood-brain barrier and on dilation of arterial blood vessels in the brain mediated by B2-receptors facilitating extravasation. Currently, LF16-0687, a novel non-peptide bradykinin B2 receptor antagonist was experimentally tested as to its therapeutical potential on vasogenic brain edema from a cortical focal lesion. Following trephination of the skull in anaesthesia, male Sprague-Dawley rats were subjected to a focal cold injury of the left parietal cortex. Animals of two experimental groups were receiving either LF16-0687 as high or low dose, whereas one group of untreated animals with trauma was treated with 0.9% NaCl as continuous infusion beginning 10 min before until 24 h after lesion. 24 h after trauma the brain was removed from the skull, and the cerebral hemispheres were separated in the median plane for gravimetric assessment of hemispheric swelling. No significant reduction of hemispheric brain swelling (+7.4 +/- 2.9%) was found in animals receiving high-dose LF16-0687 as compared to the untreated controls. Brain swelling, however was significantly attenuated by the low-dose treatment, i.e. to +6.4 +/- 1.3%; vs. +9.3 +/- 1.1% found in the controls, (p < 0.05). The current data confirm that blocking of bradykinin B2-receptors by LF16-0687 is significantly attenuating vasogenic brain edema from a focal cold lesion. The therapeutical properties of the antagonist on brain edema formation cannot be attributed to a lowering of the blood pressure. Rather, specific blocking effects of B2-receptors in the brain appear to be involved. In conclusion, the understanding of secondary brain damage including brain edema in head injury has been markedly enhanced by the discovery of pathophysiologically active mediator compounds playing a role in its various manifestations. The current data confirm a pathophysiological function of bradykinin in vasogenic brain edema mediated by activation of B2-receptors. Currently it is studied whether LF16-0687 also reduces brain swelling when given after an insult.

Animals↗
PubMed2000

[Open care--the Rodewisch theses--psychiatry enquete: 3 reform approaches compared].

AIM: The three most important German approaches for reforming psychiatric care in the 20th century--i.e. "open care" in the Weimer Republic in the 20ies, the "Rodewisch Theses" published in the GDR 1963, and the "Psychiatry-Enquete" in the Federal Republic in 1975--were compared using seven criteria. METHODS: Psychiatric and general medical journals were systematically searched for articles on aims and objectives of mental health care. RESULTS: All three approaches promoted stronger community based care. None of them suggested an "empowerment" as it is understood today. Differences between them concerned equal care for mentally and physically ill patients, international relations, and economic arguments. Comparisons on other criteria, e.g. the relationship with university psychiatry, yield a less clear picture. CONCLUSIONS: All three ideas for reforms have been successful--to a limited and different extent. They resemble each other in essential principles, but there are also substantial differences.

Community Mental Health Services↗
PubMed1999

BN 80933, a dual inhibitor of neuronal nitric oxide synthase and lipid peroxidation: a promising neuroprotective strategy.

Nitric oxide (NO) and reactive oxygen species (ROS) act independently as well as cooperatively to induce neuronal death in acute neurological disorders. Inhibition of neuronal nitric oxide synthase (nNOS) and inhibition of lipid peroxidation induced by ROS have both been proposed as neuroprotective strategies in stroke and trauma. Recently, in our laboratory, the combination of the two strategies was found to be synergistic in reducing neuronal damage. Here, we report that BN 80933 [(S)-N-[4-[4-[(3,4-dihydro-6-hydroxy-2, 5,7, 8-tetramethyl-2H-1-benzopyran-2-yl)carbonyl]-1-piperazinyl]phenyl]-2- thiophenecarboximidamide], a compound that combines potent antioxidant and selective nNOS inhibitory properties in vitro, affords remarkable neuronal protection in vivo. Intravenous administration of BN 80933 significantly reduced brain damage induced by head trauma in mice, global ischemia in gerbils, and transient focal ischemia in rats. Treatment with BN 80933 (0.3-10 mg/kg) significantly reduced infarct volume (>60% protection) and enhanced behavioral recovery in rats subjected to transient (2-h) middle cerebral artery occlusion and 48-h or 7-day reperfusion. Furthermore, treatment with BN 80933 commencing up to 8 h after the onset of ischemia resulted in a significant improvement of neurological outcome. All these results indicate that BN 80933 represents a class of potentially useful therapeutic agents for the treatment of stroke or trauma and possibly neurodegenerative disorders that involve both NO and ROS.

Animals↗
PubMed1999

Is there a rationale for rationing chronic dialysis? A hospital based cohort study of factors affecting survival and morbidity.

OBJECTIVES: To determine factors influencing survival and need for hospitalisation in patients needing dialysis, and to define the potential basis for rationing access to renal replacement therapy. DESIGN: Hospital based cohort study of all patients starting dialysis over a 4 year recruitment period (follow up 15-63 months). Groups were defined on the basis of age, comorbidity, functional status, and whether dialysis initiation was planned or unplanned. SETTING: Renal unit in a district general hospital, which acts as the main renal referral centre for four other such hospitals and serves a population of about 1.15 million people. SUBJECTS: 292 patients, mean age 61.3 years (18-92 years, SD 15.8), of whom 193 (66%) were male, and 59 (20%) were patients with diabetes. Dialysis initiation was planned in 163 (56%) patients and unplanned in 129 (44%). MAIN OUTCOME MEASURES: Overall survival, 1 year survival, and hospitalisation rate. RESULTS: Factors affecting survival in the Cox's proportional hazard model were Karnofsky performance score at presentation (hazard ratio 0.979, 95% confidence interval 0.972 to 0. 986), comorbidity severity score (1.240, 1.131 to 1.340), age (1.036, 1.018 to 1.054), and myeloma (2.15, 1.140 to 4.042). The Karnofsky performance score used 3 months before presentation was significant (0.970, 0.956 to 0.981), as was unplanned presentation in this model (1.796, 1.233 to 2.617). Using these factors, a high risk group of 26 patients was defined, with 19.2% 1 year survival. Denying dialysis to this group would save 3.2% of the total cost of the chronic programme but would sacrifice five long term survivors. Less rigorous definition of the high risk group would save more money but lose more long term survivors. CONCLUSIONS: Severity of comorbid conditions and functional capacity are more important than age in predicting survival and morbidity of patients on dialysis. Late referral for dialysis affects survival adversely. Denial of dialysis to patients in an extremely high risk group, defined by a new stratification based on logistic regression, would be of debatable benefit.

Activities of Daily Living↗
PubMed1999

Percutaneous endoscopic gastrostomy in burn patients.

BACKGROUND: Prolonged enteral feedings are required occasionally in seriously burned individuals. We have employed percutaneous endoscopic gastrostomy (PEG) in selected patients who require particularly prolonged access, thus prompting this review. METHODS: The PEG procedure was performed under general anesthesia in combination with another surgical procedure using a variety of commercially available needle and guidewire kits in 14 patients. RESULTS: These 14 patients had an average age of 55.2 +/- 6.6 years and a burn involving 38 +/- 8% of the body surface. Eleven of these patients had suffered an inhalation injury. The tubes were placed an average of 57 +/- 10.5 days after injury through unburned and unharvested skin in four patients (28%), healed donor sites in five patients (35%), healed burn in one patient (1%), and grafted burn in four patients (28%). One patient, whose catheter was placed through a grafted fascial excision, developed moderate local wound erosion. Tubes were known to have been left in place as long as 155 days. However, most were removed in rehabilitation hospitals, and we were unable to determine how long most were left in place. We are unaware of any problems with the tubes occurring after discharge from the acute care setting. CONCLUSIONS: In selected patients, PEG can provide more comfortable access for prolonged enteral feedings than nasogastric tubes and can be placed with minimal morbidity.

Adult↗
PubMed1999

Microbubbles associated with mitral valve prostheses in pediatric patients.

OBJECTIVES: To assess whether microbubbles are associated with mitral valve prostheses in children and to investigate their relationship to exercise. BACKGROUND: Bright, highly mobile echoes are seen in left heart chambers of patients with mechanical mitral valve prostheses. The clinical importance of those microbubbles is not yet known but they survive long enough to reach the cerebral circulation. No such studies have been reported in children. METHODS: There were 20 male and 10 female patients with a mean age of 10.4 years (range 2-16 years). Transthoracic echocardiography with calculation of cardiac output and ejection fraction was performed at baseline and after exercise following mechanical mitral valve replacement. Studies were evaluated for the presence of microbubbles. The mean time from operation to time of study was 18 months (range 0.2-89 months). RESULTS: Of the 30 children evaluated, 28 (93%) had evidence of microbubbles. Exercise increased the number of microbubbles in 15 of the 26 children. This was positively associated with an increase in cardiac output. CONCLUSIONS: (1) Microbubbles are commonly observed in children with mechanical mitral prostheses and are augmented by exercise. (2) This phenomenon is of a special concern in children due to their expected longevity with the prosthesis.

Adolescent↗
PubMed1999

[Physical examination and palpation findings of mammary glands and indications of udder health in goat milk].

In dairy goats there is less evidence for relationships between udder form traits, results of physical udder examinations and mastitis indicators in the milk than in dairy cows. In 413 goats (predominantly Weisse Deutsche Edelziege and Bunte Deutsche Edelziege) from five herds (free from C.A.E.) repeated investigations of 2537 udder halves and fore milk samples were carried out in order to compare udder traits with findings in the milk. Less than 20% positive bacteriological findings and a low incidence of clinical mastitis testified a good clinical udder health status of the herds. Small teat-floor distances, loose hanging of the udders and bottle-shaped teats, findings which tended to become more frequent as lactation and lactation numbers progressed, indurative alterations of the mammary tissues and the teats tended to be connected with higher milk cell counts (> 1 million/microliter), more polymorphonuclear milk cells (> 40%), higher electrical milk conductivity (> 6.8 mS/cm) and lower milk lactose content (< 4.6%). A similar effect had a bad state of foot trimming. It is proposed to include the studied udder traits into herd health programs and breeding schemes for goats.

Animals↗
PubMed1999

[Cell count and differential cell count in goat milk--variability and influencing factors].

In a total of 413 dairy goats of different breeds from five herds (milk performance 550-1000 kg) somatic cell counts and cell types were investigated in fore milk samples from udder halves, in composed udder and bulk milk samples. Cytoplasmatic particles in the milk were not counted. Three herds were investigated monthly during two years. At every sampling a clinical examination of the mammary gland (fore milk, teats, gland tissue, lymphatic nodes of the udders) and a bacteriological examination of the milk samples were carried out. In all herds the clinical health status of the udders was good. Independent of the sample type the mean SCC was about 1000 x 10(3)/ml with a wide range between several millions and < 100,000/ml. A seasonal influence on the monthly minima and maxima of the bulk milk SCC was evident, the lower SCC being recorded mainly during April to October. Increasing lactation numbers and months are connected with increasing SCC. Goats with high milk SCC at the begin of the lactation tended to maintain their high SCC levels as the lactation progressed. Limit values for SCC in goat milk should take into account the influence of the kidding season of the herds upon the dynamics of the bulk milk SCC. Polymorphonuclear leukocytes were the main cell type in goat milk (around 40%), their number tended to increase as total SCC increased, in particular in samples with cell counts above one million. Likewise, the differences between SCC in the milk of corresponding udder halves increased significantly as one of the halves showed more than one million somatic cells. Defining limit values for SCC in goat milk this should be taken into account.

Animals↗
PubMed1998

[Failure of milk ejection reflex in primiparous cows from the differential diagnostic and therapeutic aspects].

A particular failure of the milk-ejection reflex in dairy cows is described on the base of own experiences in farms and reports from literature. Four cases are reported more in detail. Quantity and fat content of cisternal, alveolar and residual milk fractions, oxytocin content in blood serum, milk-ejection after manual teat stimulation, after massage of the clitoris or rectal stimulation of the vagina and cervix were investigated. This failure of the milk-ejection is observed mostly in primiparous cows and always at the begin of the lactation period. It is complete and permanent unless successfully treated, and seems to be based on an central inhibition of the oxytocin release. Treatment consists of thorough udder stimulation and milking followed by an i.v. application of oxytocin in order to remove the residual milk portion. The condition has a good prognosis, if the treatment is carried out regularly for some days and even weeks. Acute Mastitis is the main differential diagnosis.

Animals↗
PubMed1997

Curcumin analogs with altered potencies against HIV-1 integrase as probes for biochemical mechanisms of drug action.

We have previously reported the inhibitory activity of curcumin against human immunodeficiency virus type one (HIV-1) integrase. In the present study, we have synthesized and tested analogs of curcumin to explore the structure-activity relationships and mechanism of action of this family of compounds in more detail. We found that two curcumin analogs, dicaffeoylmethane (6) and rosmarinic acid (9), inhibited both activities of integrase with IC50 values below 10 microM. We have previously demonstrated that lysine 136 may play a role in viral DNA binding. We demonstrated equivalent potencies of two curcumin analogs against both this integrase mutant and wild-type integrase, suggesting that the curcumin-binding site and the substrate-binding site may not overlap. Combining one curcumin analog with the recently described integrase inhibitor NSC 158393 resulted in integrase inhibition which was synergistic, reflective of drug-binding sites which may not overlap. We have also determined that these analogs can inhibit binding of the enzyme to the viral DNA but that this inhibition is independent of divalent metal ion. Furthermore, kinetic studies of these analogs suggest that they bind to the enzyme at a slow rate. These studies can provide mechanistic and structural information which may guide the future design of integrase inhibitors.

4-Hydroxycoumarins↗
PubMed1997

[Sleep behavior in the first 3 years of life].

A review of the literature on sleeping "disorders" in infants and toddlers shows that sleep problems are very common. We report the results of a German multicenter epidemiological study on a birth cohort (N = 1314). The children had medical examinations at 4 weeks, 3 months, 6 months, 1 year, 18 months, 2 years and 3 years. Most of the information on the sleeping behavior was gathered by structured interview and questionnaires. This paper gives information on the prevalence and the persistence of sleep problems in one to three year old children in Germany. Statistical analysis of correlations between breastfeeding and sleep and the place of sleep are reported. The consequences of sleep problems on the family overall well-being are also examined.

Child, Preschool↗